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            color: #0ff;
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    <div id="dv0">这是div</div>
    <p class="mycolor">这是p</p>
    <div id="dv1" class="mycolor">这是div1</div>
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        let a=document.getElementById("dv0")
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        console.log(b)
        let c=document.getElementsByClassName("mycolor")
        console.log(c)
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